organic compounds
2-Methylbenzene-1,3-diammonium dinitrate
aLaboratoire de Physico-Chimie de l'Etat Solide, Département de Chimie, Faculté des Sciences de Sfax, BP 802, 3018 Sfax, Tunisia, bInstitute of Low Temperature and Structure Research, Polish Academy of Sciences, 2 Okolna, 50-422 Wroclaw, Poland, and cFaculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383, Wroclaw, Poland
*Correspondence e-mail: w_rekik@alinto.com
In the 7H12N22+·2NO3−, the nitrate ions are located in the vicinity of the protonated amine groups, accepting strong N—H⋯O hydrogen bonds. Each ammonium group is involved in a total of three such interactions with neighbouring nitrate ions, generating a three-dimensional network. In addition, there are π–π interactions between the aromatic rings of centrosymmetrically related diammonium moieties, with a centroid–centroid distance of 3.682 (1) Å.
of the title salt, CCCDC reference: 982819
Related literature
For applications of amine salts, see: Jayaraman et al. (2002). For hydrogen bonding, see: Steiner (2002). For related structures, see: Garza Rodríguez et al. (2013); Gao & Ng (2012); Riahi et al. (2012). For comparable crystal packing arrangements, see: Abrahams et al. (2013); Glidewell et al. (2004).
Experimental
Crystal data
|
Data collection: COLLECT (Nonius, 1998); cell SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Berndt, 1999); software used to prepare material for publication: WinGX (Farrugia, 2012).
Supporting information
CCDC reference: 982819
10.1107/S1600536814001561/lr2121sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536814001561/lr2121Isup2.hkl
The title compound is resulting from a chemical reaction between three reagents: 2,6-diaminotoluene (C7H10N2), nitric acid HNO3 and nitrate zinc hexahydrate Zn(NO3)2·6H2O. In the molar ratio 1:2:1, 0.12 g. The amine was dissolved in a little amount of distilled water, then 0.12 g of nitric acid and 0.29 g of zinc nitrate were added. The mixture was stirred for 15 minutes and the clear solution is allowed to stand at room temperature. The slow evaporation gives rise to the formation of dark brown crystals. The X-ray analysis investigation proves that a the divalent metal is not part of the structure and that the obtained phase is (C7H12N2). 2(NO3)
Crystal data, data collection and structure
details are summarized in Table 1. H atoms bonded to N were found in a difference map and freely refined while H bonded to carbon atom were positioned geometrically and allowed to ride on their parent atom, with C—H = 0.93 Å, and Uiso = 1.2Ueq(C) for aromatic and C—H = 0.96 Å, Uiso = 1.5Ueq(C) for methyl.The amine salt family of compounds have attracted more attention due to their potential importance (Jayaraman et al., 2002; Steiner et al., 2002). In this paper, we report the synthesis and the
of a new amine nitrate salt (C7H12N2)2+ 2(NO3)-, (I). The of (I), represented in figure 1, contains one protonated diamine and two nitrate anions with general positions for all atoms. Both protonated nitrogen atoms of organic cation are engaged in hydrogen bonds with two crystallographic independent nitrate groups. So that, nitrogen atoms play the role of donor and oxygen atoms are acceptors in the model of hydrogen bond. Within these intermolecular hydrogen bonds, the D···A distances vary from 2.745 (2) to 2.960 (2) Å. Within the nitrate groups, the N—O distances and the O—N—O angles are in the normal ranges (Garza Rodríguez et al., 2013; Riahi et al., 2012; Gao & Ng, 2012). Indeed, the N—O bond lengths range from 1.235 (2) to 1.284 (2) Å and the O—N—O bond angles are between 118.42 (16) and 122.46 (17) °. These values show that each nitrate anion exhibits a slightly distorted C3h geometry. Within the aromatic rings of the organic moiety, the C—C and C—C—C angles are in the ranges 1.384 (3)—1.403 (3) Å and 115.68 (18)—123.15 (17) °. These values are comparable with those seen in other amine salts where the used amine contains a similar aromatic system (Riahi et al., 2012; Gao et al., 2012). The shortest intercentroid distance between two aromatic systems is equal to 3.682 (1) Å. This value proves the existence of p···p interactions which contribute to the crystal stability. Comparable intercentroid distances and interplanar spacing between two parallel aromatic rings, have already been observed in the literature (Abrahams et al., 2013; Glidewell et al. 2004). A perspective view of the structure shows an anionic stacking and a cationic one along the crystallographic b axis (figure 2). The obtained anionic and cationic layers, which are parallel to (-1 0 1) plane and interlinked by N—H···O bonds, alternate along [1 0 - 1] direction (figure 3).The amine salt family of compounds have attracted more attention due to their potential importance (Jayaraman et al., 2002; Steiner et al., 2002). In this paper, we report the synthesis and the
of a new amine nitrate salt (C7H12N2)2+ 2(NO3)-, (I). The of (I), represented in figure 1, contains one protonated diamine and two nitrate anions with general positions for all atoms. Both protonated nitrogen atoms of organic cation are engaged in hydrogen bonds with two crystallographic independent nitrate groups. So that, nitrogen atoms play the role of donor and oxygen atoms are acceptors in the model of hydrogen bond. Within these intermolecular hydrogen bonds, the D···A distances vary from 2.745 (2) to 2.960 (2) Å. Within the nitrate groups, the N—O distances and the O—N—O angles are in the normal ranges (Garza Rodríguez et al., 2013; Riahi et al., 2012; Gao & Ng, 2012). Indeed, the N—O bond lengths range from 1.235 (2) to 1.284 (2) Å and the O—N—O bond angles are between 118.42 (16) and 122.46 (17) °. These values show that each nitrate anion exhibits a slightly distorted C3h geometry. Within the aromatic rings of the organic moiety, the C—C and C—C—C angles are in the ranges 1.384 (3)—1.403 (3) Å and 115.68 (18)—123.15 (17) °. These values are comparable with those seen in other amine salts where the used amine contains a similar aromatic system (Riahi et al., 2012; Gao et al., 2012). The shortest intercentroid distance between two aromatic systems is equal to 3.682 (1) Å. This value proves the existence of p···p interactions which contribute to the crystal stability. Comparable intercentroid distances and interplanar spacing between two parallel aromatic rings, have already been observed in the literature (Abrahams et al., 2013; Glidewell et al. 2004). A perspective view of the structure shows an anionic stacking and a cationic one along the crystallographic b axis (figure 2). The obtained anionic and cationic layers, which are parallel to (-1 0 1) plane and interlinked by N—H···O bonds, alternate along [1 0 - 1] direction (figure 3).For applications of amine salts, see: Jayaraman et al. (2002). For hydrogen bonding, see: Steiner (2002). For related structures, see: Garza Rodríguez et al. (2013); Gao & Ng (2012); Riahi et al. (2012). For comparable crystal packing arrangements, see: Abrahams et al. (2013); Glidewell et al. (2004).
The title compound is resulting from a chemical reaction between three reagents: 2,6-diaminotoluene (C7H10N2), nitric acid HNO3 and nitrate zinc hexahydrate Zn(NO3)2·6H2O. In the molar ratio 1:2:1, 0.12 g. The amine was dissolved in a little amount of distilled water, then 0.12 g of nitric acid and 0.29 g of zinc nitrate were added. The mixture was stirred for 15 minutes and the clear solution is allowed to stand at room temperature. The slow evaporation gives rise to the formation of dark brown crystals. The X-ray analysis investigation proves that a the divalent metal is not part of the structure and that the obtained phase is (C7H12N2). 2(NO3)
detailsCrystal data, data collection and structure
details are summarized in Table 1. H atoms bonded to N were found in a difference map and freely refined while H bonded to carbon atom were positioned geometrically and allowed to ride on their parent atom, with C—H = 0.93 Å, and Uiso = 1.2Ueq(C) for aromatic and C—H = 0.96 Å, Uiso = 1.5Ueq(C) for methyl.Data collection: COLLECT (Nonius, 1998); cell
SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Berndt, 1999); software used to prepare material for publication: WinGX (Farrugia, 2012).Fig. 1. Asymmetric unit of the title salt. Displacement ellipsoids for non-H atoms are presented at the 50% probability level. | |
Fig. 2. A perspective view of the crytal structure of (I). Hydrogen atoms are omitted for clarity. | |
Fig. 3. Projection of the structure of (I) along the b axis. Hydrogen atoms are omitted for clarity |
C7H12N22+·2NO3− | F(000) = 520 |
Mr = 248.21 | Dx = 1.571 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 11810 reflections |
a = 10.494 (3) Å | θ = 3.1–27.5° |
b = 7.417 (2) Å | µ = 0.14 mm−1 |
c = 13.487 (4) Å | T = 293 K |
β = 91.46 (5)° | Prism, brown |
V = 1049.4 (5) Å3 | 0.36 × 0.30 × 0.16 mm |
Z = 4 |
Nonius KappaCCD diffractometer | 2400 independent reflections |
Radiation source: fine-focus sealed tube | 1617 reflections with I > 2σ(I) |
Horizontally mounted graphite crystal monochromator | Rint = 0.000 |
Detector resolution: 9 pixels mm-1 | θmax = 27.5°, θmin = 3.1° |
CCD rotation images, thick slices scans | h = −13→13 |
Absorption correction: analytical (de Meulenaer & Tompa, 1965) | k = 0→9 |
Tmin = 0.708, Tmax = 0.982 | l = 0→17 |
11810 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.091 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.84 | w = 1/[σ2(Fo2) + (0.057P)2] where P = (Fo2 + 2Fc2)/3 |
2400 reflections | (Δ/σ)max < 0.001 |
179 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C7H12N22+·2NO3− | V = 1049.4 (5) Å3 |
Mr = 248.21 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 10.494 (3) Å | µ = 0.14 mm−1 |
b = 7.417 (2) Å | T = 293 K |
c = 13.487 (4) Å | 0.36 × 0.30 × 0.16 mm |
β = 91.46 (5)° |
Nonius KappaCCD diffractometer | 2400 independent reflections |
Absorption correction: analytical (de Meulenaer & Tompa, 1965) | 1617 reflections with I > 2σ(I) |
Tmin = 0.708, Tmax = 0.982 | Rint = 0.000 |
11810 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.091 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.84 | Δρmax = 0.28 e Å−3 |
2400 reflections | Δρmin = −0.23 e Å−3 |
179 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.32257 (14) | 0.5382 (2) | 0.04883 (13) | 0.0161 (3) | |
H11 | 0.330 (2) | 0.416 (3) | 0.0529 (16) | 0.034 (6)* | |
H12 | 0.3819 (19) | 0.590 (3) | 0.0923 (16) | 0.029 (6)* | |
H13 | 0.338 (2) | 0.573 (3) | −0.0094 (18) | 0.033 (6)* | |
N2 | −0.03954 (14) | 0.5320 (2) | 0.27455 (11) | 0.0154 (3) | |
H21 | 0.0007 (18) | 0.582 (3) | 0.3308 (15) | 0.021 (5)* | |
H22 | −0.0346 (18) | 0.413 (3) | 0.2809 (14) | 0.023 (5)* | |
H23 | −0.124 (2) | 0.558 (3) | 0.2749 (15) | 0.031 (5)* | |
C1 | 0.02007 (15) | 0.5914 (2) | 0.18309 (12) | 0.0143 (3) | |
C2 | −0.04968 (15) | 0.7016 (2) | 0.11933 (13) | 0.0174 (4) | |
HC2 | −0.1311 | 0.7390 | 0.1357 | 0.021* | |
C3 | 0.00273 (15) | 0.7559 (2) | 0.03071 (13) | 0.0189 (4) | |
HC3 | −0.0441 | 0.8288 | −0.0129 | 0.023* | |
C4 | 0.12492 (15) | 0.7017 (2) | 0.00712 (13) | 0.0173 (4) | |
HC4 | 0.1606 | 0.7373 | −0.0522 | 0.021* | |
C5 | 0.19263 (14) | 0.5937 (2) | 0.07346 (12) | 0.0142 (3) | |
C6 | 0.14394 (15) | 0.5344 (2) | 0.16332 (12) | 0.0135 (3) | |
C7 | 0.21965 (15) | 0.4140 (2) | 0.23249 (12) | 0.0160 (3) | |
H1 | 0.3076 | 0.4499 | 0.2331 | 0.024* | |
H2 | 0.2124 | 0.2913 | 0.2103 | 0.024* | |
H3 | 0.1873 | 0.4240 | 0.2982 | 0.024* | |
O1 | 0.00268 (10) | 0.15667 (16) | 0.30012 (10) | 0.0216 (3) | |
O2 | −0.18762 (11) | 0.13185 (17) | 0.23748 (9) | 0.0237 (3) | |
O3 | −0.11592 (13) | −0.06969 (16) | 0.34182 (9) | 0.0260 (3) | |
N3 | −0.10232 (13) | 0.07181 (18) | 0.29321 (11) | 0.0171 (3) | |
O4 | 0.37995 (10) | −0.08942 (15) | 0.01918 (9) | 0.0212 (3) | |
O5 | 0.37031 (11) | 0.17901 (15) | 0.08249 (9) | 0.0203 (3) | |
O6 | 0.31797 (11) | 0.13625 (18) | −0.07227 (9) | 0.0257 (3) | |
N4 | 0.35592 (12) | 0.07296 (19) | 0.00802 (10) | 0.0158 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0172 (7) | 0.0150 (8) | 0.0161 (8) | −0.0007 (6) | 0.0037 (6) | 0.0003 (6) |
N2 | 0.0128 (7) | 0.0164 (8) | 0.0170 (8) | 0.0001 (6) | 0.0014 (6) | 0.0007 (6) |
C1 | 0.0162 (7) | 0.0126 (7) | 0.0141 (8) | −0.0036 (6) | −0.0002 (6) | −0.0014 (7) |
C2 | 0.0130 (7) | 0.0157 (8) | 0.0234 (10) | 0.0005 (6) | −0.0016 (7) | 0.0001 (7) |
C3 | 0.0192 (8) | 0.0159 (8) | 0.0213 (10) | 0.0000 (6) | −0.0063 (7) | 0.0031 (7) |
C4 | 0.0225 (9) | 0.0149 (8) | 0.0143 (9) | −0.0036 (6) | −0.0013 (7) | 0.0012 (7) |
C5 | 0.0132 (7) | 0.0118 (8) | 0.0176 (9) | −0.0012 (6) | −0.0010 (6) | −0.0026 (7) |
C6 | 0.0153 (8) | 0.0098 (7) | 0.0154 (9) | −0.0025 (6) | −0.0023 (6) | −0.0025 (6) |
C7 | 0.0150 (7) | 0.0155 (8) | 0.0176 (9) | 0.0008 (6) | 0.0019 (6) | 0.0007 (7) |
O1 | 0.0135 (6) | 0.0183 (6) | 0.0329 (7) | −0.0023 (5) | −0.0030 (5) | 0.0016 (5) |
O2 | 0.0155 (6) | 0.0332 (7) | 0.0223 (7) | −0.0006 (5) | −0.0038 (5) | 0.0015 (6) |
O3 | 0.0429 (8) | 0.0146 (6) | 0.0209 (7) | −0.0057 (6) | 0.0086 (6) | 0.0019 (5) |
N3 | 0.0184 (7) | 0.0156 (7) | 0.0172 (7) | −0.0013 (6) | 0.0025 (6) | −0.0027 (6) |
O4 | 0.0195 (6) | 0.0116 (6) | 0.0327 (7) | −0.0002 (5) | 0.0041 (5) | −0.0021 (5) |
O5 | 0.0292 (7) | 0.0166 (6) | 0.0151 (6) | 0.0035 (5) | 0.0002 (5) | −0.0037 (5) |
O6 | 0.0246 (7) | 0.0360 (8) | 0.0163 (7) | 0.0093 (6) | −0.0041 (5) | 0.0017 (6) |
N4 | 0.0124 (6) | 0.0170 (7) | 0.0181 (8) | 0.0005 (5) | 0.0014 (5) | −0.0009 (6) |
N1—C5 | 1.470 (2) | C4—C5 | 1.384 (2) |
N1—H11 | 0.91 (2) | C4—HC4 | 0.9300 |
N1—H12 | 0.93 (2) | C5—C6 | 1.398 (2) |
N1—H13 | 0.85 (2) | C6—C7 | 1.504 (2) |
N2—C1 | 1.465 (2) | C7—H1 | 0.9600 |
N2—H21 | 0.94 (2) | C7—H2 | 0.9600 |
N2—H22 | 0.89 (2) | C7—H3 | 0.9600 |
N2—H23 | 0.91 (2) | O1—N3 | 1.2703 (17) |
C1—C2 | 1.382 (2) | O2—N3 | 1.2371 (19) |
C1—C6 | 1.399 (2) | O3—N3 | 1.2475 (19) |
C2—C3 | 1.388 (2) | O4—N4 | 1.2388 (18) |
C2—HC2 | 0.9300 | O5—N4 | 1.2817 (18) |
C3—C4 | 1.389 (2) | O6—N4 | 1.2367 (18) |
C3—HC3 | 0.9300 | ||
C5—N1—H11 | 110.0 (13) | C5—C4—C3 | 118.78 (15) |
C5—N1—H12 | 110.8 (12) | C5—C4—HC4 | 120.6 |
H11—N1—H12 | 108.5 (19) | C3—C4—HC4 | 120.6 |
C5—N1—H13 | 109.0 (15) | C4—C5—C6 | 123.34 (14) |
H11—N1—H13 | 110 (2) | C4—C5—N1 | 118.67 (15) |
H12—N1—H13 | 108.4 (19) | C6—C5—N1 | 117.99 (15) |
C1—N2—H21 | 111.6 (11) | C5—C6—C1 | 115.58 (15) |
C1—N2—H22 | 110.8 (13) | C5—C6—C7 | 121.71 (14) |
H21—N2—H22 | 107.1 (18) | C1—C6—C7 | 122.69 (14) |
C1—N2—H23 | 112.2 (13) | C6—C7—H1 | 109.5 |
H21—N2—H23 | 109.3 (17) | C6—C7—H2 | 109.5 |
H22—N2—H23 | 105.5 (18) | H1—C7—H2 | 109.5 |
C2—C1—C6 | 122.68 (15) | C6—C7—H3 | 109.5 |
C2—C1—N2 | 118.10 (14) | H1—C7—H3 | 109.5 |
C6—C1—N2 | 119.22 (15) | H2—C7—H3 | 109.5 |
C1—C2—C3 | 119.49 (15) | O2—N3—O3 | 122.10 (14) |
C1—C2—HC2 | 120.3 | O2—N3—O1 | 118.62 (14) |
C3—C2—HC2 | 120.3 | O3—N3—O1 | 119.27 (14) |
C2—C3—C4 | 120.11 (16) | O6—N4—O4 | 122.38 (14) |
C2—C3—HC3 | 119.9 | O6—N4—O5 | 118.82 (14) |
C4—C3—HC3 | 119.9 | O4—N4—O5 | 118.80 (14) |
C6—C1—C2—C3 | 1.5 (3) | N1—C5—C6—C1 | 179.86 (14) |
N2—C1—C2—C3 | −178.15 (15) | C4—C5—C6—C7 | 178.77 (15) |
C1—C2—C3—C4 | −0.8 (3) | N1—C5—C6—C7 | −1.4 (2) |
C2—C3—C4—C5 | −0.2 (2) | C2—C1—C6—C5 | −1.1 (2) |
C3—C4—C5—C6 | 0.6 (2) | N2—C1—C6—C5 | 178.57 (14) |
C3—C4—C5—N1 | −179.28 (15) | C2—C1—C6—C7 | −179.79 (15) |
C4—C5—C6—C1 | 0.0 (2) | N2—C1—C6—C7 | −0.2 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H11···O5 | 0.91 (2) | 1.85 (2) | 2.746 (2) | 168 (2) |
N1—H12···O1i | 0.93 (2) | 1.93 (2) | 2.845 (2) | 168 (2) |
N1—H13···O3ii | 0.85 (2) | 2.07 (2) | 2.891 (2) | 161 (2) |
N2—H21···O5i | 0.94 (2) | 1.91 (2) | 2.808 (2) | 161 (2) |
N2—H22···O1 | 0.89 (2) | 1.96 (2) | 2.839 (2) | 172 (2) |
N2—H23···O2iii | 0.91 (2) | 2.05 (3) | 2.958 (2) | 174 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) x+1/2, −y+1/2, z−1/2; (iii) −x−1/2, y+1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H11···O5 | 0.91 (2) | 1.85 (2) | 2.746 (2) | 168 (2) |
N1—H12···O1i | 0.93 (2) | 1.93 (2) | 2.845 (2) | 168 (2) |
N1—H13···O3ii | 0.85 (2) | 2.07 (2) | 2.891 (2) | 161 (2) |
N2—H21···O5i | 0.94 (2) | 1.91 (2) | 2.808 (2) | 161 (2) |
N2—H22···O1 | 0.89 (2) | 1.96 (2) | 2.839 (2) | 172 (2) |
N2—H23···O2iii | 0.91 (2) | 2.05 (3) | 2.958 (2) | 174 (2) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) x+1/2, −y+1/2, z−1/2; (iii) −x−1/2, y+1/2, −z+1/2. |
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